RSV (Respiratory Syncytial Virus/Bronchiolitis)

From 1 September 2024, pregnant women can have a free vaccine in each pregnancy, to protect their babies against respiratory syncytial virus (RSV).

RSV is a common virus which can cause a lung infection called bronchiolitis. In small babies this condition can make it hard to breathe and to feed. Most cases can be managed at home but around 20,000 infants are admitted to hospital with bronchiolitis each year in England. Infants with severe bronchiolitis may need intensive care and the infection can be fatal. RSV is more likely to be serious in very young babies, those born prematurely, and those with conditions that affect their heart, breathing or immune system.

More information on bronchiolitis can be found here.

How the RSV protects your baby

The vaccine boosts your immune system to produce more antibodies against the virus. These antibodies then pass through the placenta to help protect your baby from the day they are born. RSV vaccination reduces the risk of severe bronchiolitis by 70% in the first 6 months of life. After this age your baby is at much lower risk of severe RSV.

Older children and adults can also get RSV infection, but the disease is more serious for small babies and people aged 75 and over.

The vaccine has been shown to reduce the chance of your baby suffering from severe RSV disease. Like all medicines, no vaccine is completely effective and some babies may still get RSV infection despite their mothers having the vaccine. However, for most babies born to vaccinated mums, any RSV infection should be less severe.

When you will be offered the RSV vaccine

You should be offered it around the time of your 28 week antenatal appointment. If you haven’t heard by this stage, contact your maternity service or GP practice to make an appointment. Having the vaccine in week 28 or within a few weeks of this will help you build a good level of antibodies to pass on to your baby before birth. This will give your baby the best protection, including if they are born early.

You can still have the vaccine later in your pregnancy but it may be less effective. If it wasn’t possible to have your vaccine earlier, it can be given right up until you have the baby. If you have it very late in pregnancy, it may still protect you from infection and reduce the risk of you spreading infection to your newborn baby.

You will be offered the RSV vaccine during every pregnancy

Having the vaccine during each pregnancy will offer your new baby the best protection from RSV.

The safety of RSV vaccination during pregnancy

The vaccine has been studied in clinical trials of almost 4,000 women and been given to many thousands of women in national programmes. Monitoring in the USA, where it has been given to over 100,000 women, has shown a good safety profile. In the main clinical trial, in the month after vaccination, there were slightly more premature babies in the vaccine group (2.1%) than the group that didn’t have the vaccine (1.9%). This difference is most likely to be due to chance.

The vaccine has been approved by medicines regulators in the UK, Europe and USA on the basis of protection, quality and safety.

Babies at a higher risk of RSV infection

Some babies are at higher risk of RSV, such as those who are very premature, those with severe heart disease or those with weakened immunity. They may also be offered an antibody injection. This injection will provide additional protection on top of any antibodies they might get from their mother.

Having the RSV vaccine at the same time as other vaccines

It is important to have your vaccines at the right time in pregnancy

Whooping cough (pertussis) vaccine

The whooping cough vaccine is usually given earlier in pregnancy. Around the time of the mid pregnancy scan, usually 20 weeks.

Flu vaccine

Flu vaccine can be given at any stage of pregnancy. You should have it as soon as it becomes available to you.

When you are called up for your RSV vaccine, if you have not yet had your whooping cough or flu vaccines, then you should have them at the same time.

Side effects from the RSV vaccine

The vaccine is a single injection in your upper arm. Side effects are usually mild. These may include:

• headache
• muscle ache
• soreness, redness or swelling at the site of the injection